If water is stored over longer periods of time in a container, microbe cultures may form and grow even in the case that there is only a poor presence of nutrient matter. Development of microbe cultures is visible as a formation of bio-films. Bio-films exhibit a jelly-like consistence. In many cases, the occurrence of bio-films is associated with a nauseous appearance and with a disturbing smell. In the worst case, a health hazard cannot be ruled out.
In laundry dryers, fluff is inevitably formed in a drum during a drying process because of a friction or rubbing of clothes or laundry pieces with each other. This fluff is swept along with the process air. If the process air is cooled down to reduce its absolute humidity, it condensates such that part of the water contained by the process air is segregated as condensate. This condensate is temporarily stored in a condensate container before it is either discharged from the laundry dryer or reused, e.g. as a cleaning fluid for cleaning a filter and/or a heat exchanger.
Operation of the laundry dryer, however, may be affected by presence of the fluff. For example, the fluff attaches itself to surfaces of a heat exchanger during condensation, which reduces an efficiency of the heat exchanger. Also, the fluff may be swept along by the condensate and agglomerate in the condensate container. This, in turn, may lead to the formation of bio-films in the condensate container.
It is thus a desire to reduce the presence of fluff in the condensate container. The bio-film in the condensate container may act as kind of “glue” that promotes a further agglomeration of fluff. The agglomerated fluff may be the cause for other disadvantageous effects. For example, the agglomerated fluff may cause pumps to get blocked. It may also cause short circuiting of electrodes of a filling level sensor of the condensate container. All these effects may lead to customer service deployments, related costs and subsequent customer dissatisfaction.
To prevent fluff from reaching the condensate container, it is known to place fluff filters in a process air channel between the drum and the heat exchanger for cooling down the process air. This has the disadvantage that the fluff filter must be cleaned regularly to avoid blockage of the process air channel. To automatically perform this cleaning, a complex arrangement is necessary, e.g., comprising pressure pumps, separate fluid channels etc. Also, the fluff filters cannot completely withhold all fluff such that still a small portion of the fluff may reach the condensate container to act as culture medium for microbes.
It is known that very low concentrations of dissolved ions of certain elements, especially of Group Ib elements Cu, Ag and Au (also called copper elements) show a strong oligodynamic effect. The oligodynamic effect describes the fact that the presence of these elements inhibits or at least slows down a growth of the microbe cultures to a high extent.
The oligodynamic effect is e.g, used by the application of Ag ions for interior parts of a refrigerator to inhibit formation of microbe cultures inside the refrigerator and to avoid a nauseous appearance and/or to prevent accelerated spoiling of food. Other application of the oligodynamic effect is plant protection. Low concentrations of Cu act as a very effective protection against attacks by fungi. In another application, it is reported that Au as filling material in dental applications significantly reduces caries development.
U.S. Pat. No. 7,624,601 describes a water feeder which is configured to add low concentrations of oligodynamic material to the water used in washing machines in order to counteract the formation of microbes. A water feeding apparatus has an ion eluter and a shower emitter. The shower emitter receives water via a coupling pipe from the ion eluter, and sprays the water, in the form of a shower, onto laundry. Liquid droplets in the form of a shower are small and easy to dry, and thus produce crystals having smaller particles (with large surface areas), having more lattice defects, and easier to dissolve. With these crystals attached to the laundry, when the crystals make contact with moisture next time, the silver ion in the liquid droplets easily dissolves. Even when the laundry is made of water-repellent or hydrophobic cloth, the solution dries up on the surface of the cloth before water is repelled. Thus, even this type of laundry can benefit from the antimicrobial effect of the silver ion.
EP 2 079 870 B1 discloses an iron comprising a soleplate having a garment-contact surface, wherein the soleplate has means for accommodating an antimicrobial agent, wherein said means for accommodating an antimicrobial agent comprises said garment-contact surface, whereby said garment-contact surface accommodates said antimicrobial agent and is arranged for transferring the antimicrobial agent to a piece of garment.
EP 2 009 166 B1 discloses a control for an automatic washer to operate the washer through a wash cycle determined based upon various soils and stains in the substrate load to be washed with a wash liquor in a wash zone of the washer, the control comprising: a plurality of stain/soil type entrees, which can be at least one of selected and detected, and cleaned with a particular wash cycle, dispensing control over the addition of oxidizing agents to the wash liquor, wherein there is dispensing control over at least one wash liquor additive from the group consisting of detergents, chlorine bleaches, color safe bleaches, cleaning boosters, pre-wash stain removers, pre-wash chemistries, switchable or tunable surfactants, wrinkle guard, color finishes, water repellency, stain guard, functional finishes, fabric softeners, water softeners, fragrance, anti-static agents, drying aids, de-wrinkling chemistries, deodorizers, surfactants, emulsifiers, enzyme activated stain removers, sudsing agents, builders, anti-redeposition polymers, in-wash stain removers and perfumes, operational control over activators and deactivators for members of the additives group, the activators and deactivators being from the group consisting of thermal, biological, chemical, electromagnetic and mechanical actions, and operational control over the particular wash cycles using the dispensing control to dispense additives to the wash liquor at selected times during the wash cycle and operating the activators and deactivators at selected times during the wash cycle. A wash cycle comprising the steps: loading a wash machine with a substrate load for cleaning, selecting a wash cycle based on at least a stain/soil in the substrate load, contacting the substrate load with a wash liquor, dispensing a wash liquor additive into the wash liquor, wherein the group of additives consists of detergents, chlorine bleaches, color safe bleaches, cleaning boosters, oxidizing agents, pre-wash stain removers, pre-wash chemistries, switchable or tunable surfactants, wrinkle guard, color finishes, water repellency, stain guard, functional finishes, fabric softeners, water softeners, fragrances, antistatic agents, drying aids, de-wrinkling chemistries, deodorizers, surfactants, emulsifiers, enzyme activated stain removers, sudsing agents, builders, anti-redeposition polymers, in-wash stain removers and perfumes, and selectively activating or deactivating the dispensed additive with activators and deactivators, the activators and deactivators being from the group consisting of thermal, biological, chemical, electromagnetic and mechanical actions.
WO 2007/145451 A2 discloses a dryer and a method for controlling the same. The method for controlling a dryer includes a steam supply step for supplying steam generated in a steam generator to a dram, and a hot air supply step for supply hot air generated in a hot air heater to the drum. The method may have an advantageous effect of removing wrinkles efficiently.
U.S. Patent Publication No. 2010/0212369 A1 discloses a device for cleaning an evaporator of a condenser with condensation water. The device includes a condensation water pan that collects condensation water condensed from process air by the evaporator, and a collection container above the evaporator that receives the condensation water from the condensation water pan and that dispenses the condensation water with a gush onto the evaporator from a rinsing chamber of the collection container with a sudden opening of a closure part through a downpipe.